Its in a nice location but food was very pricey and to be honest not some of the best but its all about personal tatse and we all have our favourites.
Best thing your friend could do is try it on the first night before they book it. Unless its really high season there shouldnt be much need to book much in advance. Best ones for me are the Seaside which is at the start of Kamari and often gets forgot about with people out walkign at night. We have been to Kamari several times and most have tried them all..lol
Another popular place for wedding receptions is the Mexican called Senor Zorba which is right on the caldera with fantastic views and really good food.
Somemore good ones in Kamari are the Boat House Taverna and Almiria next to The Seaside and Syrtaki

Atmosphere is a very nice restaurant with a touch of class and, for me, is a great place for a wedding reception. It has lovely lighting, a good choice of food and is really nicely decorated. In comparison to other tavernas in Kamari it is more expensive, though not extortionate and it is a wedding reception eh?

Places like Senor Zorbas are a bit tacky looking and miles away from Kamari. Almeria is nice and does really nice food but not sure it has a 'wedding reception' type feel about it.

thats why I said its all about personal taste...Zorbas is about a 10 minute drive away not excatly miles away and the setting is well worth the drive but agree it might not be the perfect place for a reception.
Almira and Seaside both had wedding receptions while we where there last time and they did a great job but thats for me because I love the family feel to those places rather than some of the other places in Kamari . I still think its a good idea to try before you buy for such an important thing like a wedding reception even if your doing it in this country I wouldnt go blindly without first testing it out for such an inportant occasion