But why suspect that it is not reliable in the first place?

I only have experience with TER, and so far I have found TER to be very reliable.

The only way to tell with another site is to see gals from there and find out for yourself.

Without knowing which site it is, none of us can answer that. Some are reliable, some aren't. If you have the time, give the other site a thorough read, and see if her reviewers on there seem to be established and respected (have a posting history, have other reviews of ladies you know to be bonafide).

As mentioned above, check out her reviewers on here too -- are THEY reliable? If so, she's probably ok. Remember that it can be relatively tough for a provider on TER to get reviews posted, especially if she's new to the site or TER isn't very popular in her area.

Many geographic areas prefer other review and verification sites