The company I work for, a US based, low cost, A-320 operator, has used laptops from day one. From study software, to manuals, to performance calculations. Personally, I have found this to be great.
We, the pilots, do the wt&Balance and then the perf. calculations and it sure beats waiting for new paperwork from the company. Or interpolating a chart. Want an intersection takeoff, no problem, give me five seconds. Last minute bags, give me five seconds.
Your manuals are up to date, no waiting for revisions through the mail. I actually have all the company manuals on the computer and can reference them all, should the need be.
We are currently in the works of getting approach plates on the computer as well and honestly, I cannot wait to get them.
As far as system maintainability, I have had very few problems indeed with the computer itself or the software. We do carry two computers, one for each pilot, so redundancy there. Further, should both cause roblems (unlikely) then dispatch/Ops, has several as well.