Bought my machine of them and voice my opinion many times on the forums....
They are extremely convenient - go and collect it off the shelf!
A big business that will be here tomorrow and the day after.
Depending on how the stores run, you can get oodles and oodles of good honest help.
One guy imparticular at my local is one hell of a sales guy, knows everything, a pleasure to talk to.
Had my machine 8 months now, a Compaq, and it has given ROCK solid performance it gets used and abused 15 hours a day, every day. Only one crash due to dodgy mouse drivers that I installed and qucikly removed again.
I would recommend them, though you should do a bit of research before buying a PC not just from PCW but anywhere...