Here is a general list of things, from a client point of view, what really every host should strive for, and what every client should be looking for in a host.
1. choose a VPS provider who's datacenter is geographically close to your target audience. Also a host that is fairly close to you, since you'll be the one accessing the VPS the most.
2. don't necessarily choose a host with the "fastest" ticket response time, but choose one who you feel you communicate well with. A host who understands your specific needs, and who can sit down with you and talk about what your needs are, and how that host can accommodate for those needs.
for example, when I started looking for a host, my needs were small..
VPS with cpanel/Fantastico/RVSkin
10 mb disk space
5 GB transfer (to start, or more later as my traffic grew)
basically yer average "small" VPS.. Well, after I signed up for a host, I started to notice even those limits were way above what I needed. I was only getting 450 mb of transfer (not even a gig) and my disk space was wayy under 10mb, more like 2mb at best.
but yet, I kept noticing numerous RAM issues. So I asked my host, I was like..."why do I have such little traffic, yet the 256mb guaranteed, 1GB burstable, isn't enough, that just doesn't make any sense?"
Well, I opened a ticket about it, and we sat down and discovered I probably needed more RAM, so they gave me more, but then I was still having the same issues even with 2x that amount, so the hosting provider investigated why I was having RAM Issues, and not only kept me at that limit, but then also discovered why I was having RAM issues and fixed those too.. It ended up being cpanel related, but if I hadn't have bothered to ask, I would have just assumed it was the host and went on to someone else, in fact I almost did until I realized that it actually was a configuration issue, so its "very" important for you to be able to communicate with your host well, because they want your site up just as much as you do, because it looks good on them as a company. If they blow you off, or don't listen to your specific needs, don't be afraid to go somewhere else, because its very important for a host to do that, no matter what the size of the company is.
3. Make sure the host has the payment option your looking for. I don't even think twice about a host that doesn't accept paypal. Its not that I don't trust anyone, well people I've never met face to face in person I don't trust, and have every reason not to, for you don't know what the company is really like, you don't really know if they exist at all.. I don't even trust my wife to have my credit card #, do you think I'm going to trust a web hosting provider with it? heck NO.. I'm sure a hosting company wouldn't just steal my money from me, but then again, you never know, but for me, its just the point of the matter, I want a host who can accommodate for my needs, and paypal is something I feel is important, and if its important to me, it should be important to them as well, right? because a host should want your business, not lecture or try to blow you off.
which brings me to something even more important
4. don't go with a host that just has "set" plans and thats it. Each person has different needs.. In my above example, what if I wanted 5mb disk space, 5gb transfer, something really small, but wanted 512mb guaranteed RAM? could a host compensate without necessarily try to sign me up for an $80/mo plan with 20mb disk space, 500 GB transfer, etc etc? I mean, why give me high specs that I'll never even come close to using, when all I need is 5mb disk space and 5GB transfer, and just some extra RAM, right? can't they just give you more RAM at, oh I dunno, 2-3 dollars more a month, instead of like $20-30 more for all those specs I never use? I mean, thats just ridiculous, and its very important for a host to be able to setup a specific plan for a specific client like that.
Just make sure, whoever you pick, to do your homework. Web hosting is kinda like going on a job interview.. "its all about being at the right place at the right time." just because 50 other people may have bad experiences, doesn't mean you will. Don't let other peoples experience decide for you, listen to what other clients say, and decide for yourself. I've switched hosting providers a dozen times, there's nothing wrong with that, so long as you find a host that you like thats whats important, not what anyone else thinks