Hi ioFinImports,
Since I haven't dealt with wholesaledeals.co.uk personally, I thought I'd so a quick search on them.
They seem quite legit and have been online since 2003. They are actually a directory pretty much like SaleHoo offering their members access to a list of wholesale and drop shipping suppliers. Their member ship fee is also a bit high, like for their basic package you are required to pay GBP100/year. Although I could not find any direct negative reports about them, they seem to be associated on the net to another site esources.co.uk.
They accept safe payment methods such as PayPal and major credit cards.
Hope this helps.
Cheers :)