Has anybody had any luck with this website

Just taken a look - If they don't reply to emails, I wouldn't touch them What will happen if you have a problem?

I think they're a scraper site that copies other site's listings for sale then gets paid a fee from the agent if they send a buyer to them, not actual estate agents themselves. If you see something there you like, trying doing an internet search using the wording from the listing.
The other thing to check on that site is the age of the listing - each will have a date it was last updated. A house listed 12 years ago and sitting empty since will probably be in a far worse condition now. Plus I doubt they pull listings when houses sell, either.
It's interesting to look at to get an idea of the market and saking prices, but going straight to the real agent is probably a better idea.

I dealt with them a few years ago. The owner actually lives here in the Uk although appears to be Bulgarian.
I viewed a few houses and all seemed legitimate. It may have changed hands by now of course but they were always prompt in their response and helpful.
A bit like some UK agents,  he seemed to contact the owners of the properties to do the viewing rather than having agents in Bulgaria but I did not get a sense of anything untoward at that time.

Don't use agents  most blow up prices for newby expats their completely unregulated so good luck with them. Consider buying direct from exciting expats. I have 3 houses for sale cheap. What are you looking for and where?

Hello

Where how much.

They didn't answer any of mine either so I've stopped enquiring

Hello,
I am from Belgium. There was a French phone number. I contacted them by phone and then I asked for information about two houses. They answered me each time within a week. The lady had a Bulgarian accent but spoke good French.
I am only going to February to visit so I don't know if it is reliable.