SOMEBODY RESCUE THIS GUY FROM THE ANTRON99 DUMMU LOAD ANT!!
WAIT!!! HOLD IT!! - If IMAX-2000s are still available get one of those as I and several friends have tested them, one against the other, and seen TWO FULL 'S'-units gain from the Antron99 to the IMAX-2000 PLUS much less TVI from the IMAX!!!!!!!!
(on my Kenwood TS-930S meter)
I have given away (thank the Lord!!) every Antron99 I had (7 of them came my way...poor me!!!) and have set up my friend Donn with my old IMAX which he said has transformed his station performance to what he thought he would need a beam to get in comparison to his old Antron99... which he gave me.
...and I thought he was a friend 
And another thing, if you get an IMAX and can drill a small hole thru the top of the aluminum mounting tab / bracket so you can add 3-10 or more 8' 6" radials (centered on ch.40) made from wire, even guy wire, to an insulator and hanging down at ~60* angle, you should get even better performance, especially at a distance, along with even less TVI!
Let us know what you end up with & how well it's working for you.
73!