Monobander vrs tribander

[gliderking at aol.com]

I am a qrp contester except when trying to work the likes of 3y0pi (that
required 100 watts!) and have a question for you seasoned fellows. I live in
a suburban area and currently have a light duty tower that supports about 5-6
sq. ft of antenna safely at 65 feet. I have shunt loaded the tower for 160
through 40 and it works very well for dx on the low bands. Now with the sun
gods leaving for the next 5 or 6 years I am thinking about replacing my A3 (3
element tribander, 14 foot boom with 40 meter extension on driven element)
with a full sized 20 meter monobander. This would be limited to 3 elements on
a 18 to 20 foot boom to keep the wind loading acceptable. As the realistic
gain of the a3 on 20 is likely 4 to 5 db the 7-8 db of the monobander should
give an honest 3db gain in the real world......right? Your comments, form
expeirience or theory appreciated. Is it worth the change?
Thanks, Dr. Rick Zabrodski VE6GK  Gliderking at aol.com