Greg,

IF the only circuit published by the device manufacturer is for an amplifier
operating below 30 MHz,
that's a pretty good sign the devices won't provide any gain at 50 MHz...

BTW, a good 6 meter yagi (which is very easy to build and much smaller than
10 meter beams)
will yield more dB increase for less dollars than the amplifier.
Not totally true.

We use a THA15/SD1726 (30MHz bi-polar 150w pep) producing 220w in our FM
PA in continuous duty service in the 87.5-108MHz broadcast band.

Yes, it needs plenty of drive and the heat sink require plenty of air
but at $30 USD a hit it's one economical and rugged amp.

Here it is: http://www.transmittersrus.com/shop/powerRF220.htm

I totally agree with you on the antenna.

(((73)))
--
Philip de Cadenet G4ZOW
Transmitters 'R' Us
http://www.transmittersrus.com