Just the same as other hosting - look at their uptime, support times, features.
Also remember to look at the number of domains you can host etc, which will be more important on reseller accounts. I'd pay attention to the features they provide - my host supplies WHM so it's all point-and-click to set up new accounts.
If you opt for reseller plans, then don't bother about the cost and your focus should be on reliable and quality service. You need to have a check on features provided in the particular plan such as 24/7 tech support,24/7 live chat and phone support and additional 30 day money back guarantee if you don't like the service.
You should go through EUKHost, resellerspanel plans.
Before deciding on a reseller host, you must be able to mark which type of websites will be your primary need.
Search for a reseller host that offers the best possible technical and client support.
A reseller host that has credibility in the market is always a better choice than those with spurious reputations. It is best to be careful with those that offer improbable benefits like unconstrained disk space and bandwidth.
Linux Reseller Hosting is a very popular hosting solution for most web resellers.In reseller website hosting, the real web hosts are capable to generate the bulk business as well as delegate the clients for reselling the servers. In return, the reseller hosting business looks after the needs of the individual clients.