Miromiric - Laptops are quality - don't believe the guys that knock 'em.
More and more touring djs are playing out live using Final Scratch, so they must be getting more reliable. They can still be a bit unpredictable, but well worth the investment.
About 6 months ago, I was in the same position as you. It took me probably about 3 months to finally decide what route to go down.
You have 3 realistic options before you...
a) By a mac Powerbook (at an incredibly inflated price.) Bear in mind that apple bulletproof stability is no longer what it was...
b) By an Intel Centrino based machine
c) by a P4 or AMD driven machine.
Things to consider are what you plan on using it for. Centrinos offer tremendous battery life, and much lower fan noise as they operate at a lower temperature, and hence offer a very portable solution. However in opposition to these benefits are the fact that processing capability, when compared pound for pound/dollar for dollar with Intel P4s is not favourable. Also, Centrinos are significantly more expensive. The fastest Centrinos cannot compete at all with the fastest P4s, so if you basically want a Desktop replacement machine, you should maybe be looking at a P4. P4s probably offer a more stable environment as they providepotentially faster processingbut P4s have their problems too. Fast processing means a very hot processor, which in turn means the fan coming on all the time, and possibly producing a lot of noise. Additionally, the keypad may get quite warm as a result of all this heat. A noisy fan can be major problem if you are recording from microphones etc in the same room as your lappie. Something to consider...
Also, key to good performance with audio in is hard drive speed. Most models kicking about just now have hd speeds of 4200 rpm, or 5400 rpm.
Try and get as fast a hard drive as you can. My machine has a 7200rpm 60gb hd, but I think you can get hd that run at 9400rpm, though you will be paying through the nose for this kind of performance, and it will most likely be a noisy bastard!!!
Celerons, and AMD based systems I don't know too much about. Celerons appear to be the budget alternative, and AMDs get mixed reviews. Some people absolutely love their AMD machines - very fast processing at a very reasonable price. Somethign to consider though is that P4s seem to be the preffered platform that Steinberg use to build Cubase. As far as I know, AMDs aren't used, and hence this is why AMD machines can prove to be a bit less stable than comparable Pentium systems.
Another thing to consider is upgrade path. If you plan on having your machine for a good amount of time, it possibly makes sense to give yourself a good option for upgradeing. What you need the machine to do today, may not be exactly the same as what you want it to do in a months time. This is where Celerons let themselves down. I was very close to buying one, thinking that I could buy an entry level Celeron machine, and in a years time upgrade to a faster chip in a years, when the prices beging to come down. The problem with most entry level Centrino systems is that You can only upgrade to a 2 ghz centrino chip. This is because all the subsequent chips operate at a differrent voltage (or something) meaning that if you want to upgrade to a 2ghz+ chip, you will most likely need to replace your motherboard as well. Considering the entry level Centrinos come in at 1.5 ghz, it doesn't leave a hell of a lot of space to manouver if you ever want tremendous processing power.
Bare in mind that also it helps if you have a good graphics card in your machine. If you are using it to do audio, this will obviously free up CPU for running your audio programs and plugins.
So, finally I decided to go for a Pentium P4 system.
I purchased my machine from a UK company - www.NuSystems.co.uk
and wasn't dissappointed. Very friendly service, and almost always very quick with any replies to my queries via email.
My system spec - P4 3 ghz. 512meg, 128meg graphics, 60gb 7200rpm HD.
Nusystems are computer audio specialists, and also do tweaks to XP and the BIOS (I think...) to provide optimum performance when using audio programs. Additionally I asked them to give my machine a "dual-boot" set-up. Essentially a dual boot system is one where you have 2 versions of your operating system on your machine. For example I have an "Audio" boot partition which sets my machine up for optimal audio performance, but I also have a "General" boot partition which is set up for general web surfing, and game playing.
There are other good audio specialist builders, like red sub, millenium, and alienware make specialist machines with quality components, but you they are all really expensive. The aftercare with these guys is probably second to none however. I don't know for sure. I haven't had to use any aftercare with Nusystems because I haven't had a problem in the 3 months I've had it.
Obviously 60gb for a hard drive isn't a lot of space so I want santa to bring me a nice big 200gb external drive, and definitely another 512 meg ram. The 512 I currently have is ok, but for running high CPU programs like any of the Spectrasonics VST plugs, you really need the extra memory.
One last thing to think about, and this is where things do complicate further is your soundcard. There are a good few on the market suitable for use with a laptop, and they also vary wildly depending on what you plan on doing. They can be quite an additional spend though.
The best thing to do is set yourself a budget ceiling, and then tailor what you want respective of whether you can afford it or not. Remember, bits and pieces like memory you can always buy yourself from Crucial or the like, further down the line when you have more money. You don't need to buy it all at once from the same shop, as they will take their skin from any component used to make up your machine, and hence bumping up the price...
I hope this gives you some food for thought. Do your research like I did, and you will always be more comfortable with what you eventually buy, and less likely to get the "buyer's remorse". check out Sound on Sound forum for further research - always a good place to pick up tips...
http://www.soundonsound.com/forum
I'm away for a sleep - my brain's fried.....
BombJack