Have you tried asking your current suppliers if they dropship? I've found that many wholesalers will dropship if you ask them, but they don't advertise the fact.
The problem with the large dropshippers is that so many other people are selling the same goods. If you look on eBay, you'll usually find loads of other sellers with the same stock all trying to undercut each other. Not only do they all have the same stock, but many of them use the same photo, but worst of all, if they use the dropshipper's product feed, their product descriptions will be identical which won't do them any favours with the search engines.
I'd rather use more than one dropshipper as relying on one company for your whole business leaves you vulnerable. The disadvantage of using more than one is, if a customer makes a multiple purchase and the stock comes from different suppliers. Obviously in this situation, there will have to be two more than one delivery and you won't be able to offer a discount on the postage (unless it's a big enough order to make it worth your while to swallow the extra cost).
There are some dropshippers that will allow you to view their price lists without subscribing, but others I've seen charge £50+/yr before you can even look at their full product range. I wouldn't part with a penny until I knew exactly what I could get and at what price from them.
Also, be wary of any that post testimonials from "satisfied customers" as all may not be as it seems, check the link below for an example.
http://www.netprofitstoday.com/blog/...pship-example/
That's what you call getting caught red handed!