I've done some research and seen some reviews around 4.5 to 5 stars but not 100% sure they're genuine.
Don't mind going to a parlour or incall.
Where have you found those reviews? Neither of the two main review sites, svetaci or tapky, do starred reviews. If they are reviews on an agency site, I would treat them with the same caution as reviews on UK agency sites, i.e. they only publish the positives, and if there aren't any, they make them up.
If you want comments on a particular establishment or agency that you have found, feel free to post a link here, Otherwise most of my recommendations based on decades of visits to Prague can be found on these threads:
https://www.ukpunting.com/index.php?topic=431111.0https://www.ukpunting.com/index.php?topic=364967.50In a Prague massage parlour, the only extra that you are likely to get is a HJ. If you want more, you need to go to a privat. These charge the same kind of rates as parlours, but you get FS. But you need to be aware that because Prague is a city built on tourism, there are many establishments of all types whose business model is to rip off gullible tourists. I include most of the clubs in that category.
Public transport in Prague is so easy to use, especially the trams. You really haven't experienced Prague if you haven't travelled around by tram. Buy yourself a 3 day pass at one of the ticket machines at the airport bus stop, pop it in one of the yellow validators on the bus, and you are good to go. So I wouldn't worry too much about sticking to the old town area. In fact, I would advise against it, as that area is notorious for tourist ripoff establishments.