Not all directly relevant to your specific question, but...
I just built my new PC, been nearly 5 years since my last, so many changes, and yet - the same rules still apply. SSDs are faster than spinning drives, but data bandwidth still applies, particularly for larger file operations, check what bandwidth your system supports (1.5, 3, or 6 gb/s). SSDs are much more reliable now but any drive can fail, if your data is important back it up, remember the 3, 2, 1 rule, 3 copies, 2 different types, 1 copy offsite. People may mention RAID and NAS solutions, RAID is not backup, it is redundancy, it might save data that would otherwise be lost, but don't rely on it, and NAS can be used for backup, but don't rely on it as your only backup. Cloud solutions, or blu-rays stored in another location (bank deposit box, with a family member etc) are good offsite options.
Do your research, small SSDs are generally poorer than larger ones, many ranges 128gb drives do not measure up vs the same lines 256gb models. Budget is usually the deciding factor, but don't be fooled into false economy.
If you need a large capacity in a laptop hybrid is probably your best choice, a simplistic split between o/s, apps, and data is fine for average users, but with some time and effort a customised split will offer better performance, the o/s will usually be on the SSD partition, but choose carefully which apps and data goes where, some apps and data will benefit more than others, consider frequency of use, the size and complexity, your music can all go onto the spinning drive partition, as can small apps you or ones you rarely use, while your favourite hi-def video might take up a lot of space, it will also play more smoothly from the SSD partition.
My new PC is set up with 3 drives, 256gb SSD for windows and main apps, 512gb SSD for games, and 2tb spinning drive for data and large apps I use infrequently. The o/s drive has a backup image on the data drive, while key data is backed up to an external drive. Static data is also copied to blu-ray, dynamic data to cloud services (google drive, skydrive, etc).
I noticed a number of replies included some manufacturers and models, for reference, my SSDs are Samsung 840 pros, the spinner a WD Caviar Green, if I needed more performance from my data drive I would have gone with a Caviar Black instead. All drives are sata 6gb, with full support from the motherboard. My own research showed OCZ vectors would have been good alternatives, or the latest vertex models, these are all fairly premium models though.
Personally, if I had a laptop which supported sata 6gb and had USB 3, I would put in an 840 pro or vector 512gb and take along a large USB 3 external drive if I needed more space, if the budget doesn't stretch that far then a good hybrid, ideally with 256gb of SSD.
To your specific question - long term reliability of SSDs is good enough for all but the most technophobic, you will be replacing your laptop long before your SSD is likely to die (exceptions can always happen). Performance-wise there are only a few measures, read and write speeds for small and large files being the main 4, manufacturer stated read/write figures and IOPS (a technical measurement) can be used as a guide, but do not always translate directly to actual performance. Use a good review site - pcper.com, toms hardware, and of course, here at c|net, to find the best choice for your budget and system, but remember to consider your systems other capabilities, the upgrade to SSD can make a big difference, but there are many other choke-points that limit your systems performance