Thanks everyone for your replies. I played on Tuesday and finally decided to join a golf course. While I was completing the membership application I noticed a "new" set of lefty Taylormade RBZ Irons in the office. They looked virtually brand new. I was then offered to take the iron set with me for the round but opted only for the 7 iron. I played almost the entire round without taking this club out once until the 18th hole when I was laying 156 yards from the center of the green whereas the pin was located half way between front (140ish) and center.
I currently hit my MP60 7 iron about 150 yards. I also play my irons quite high with a small cut. I hit my first shot with the MP60 and was pin high approximately 20 feet away; total distance was 145 yards. I finally hit the RBZ 7 Iron. Wow, I couldn't believe how easy this club was to hit! I played my normal shot but hit the ball dead straight and long as it was on the back in the first cut. I then decided to play a few more holes and hit this club a second time. I was in the rough 160 yards away to the front with an obstructed approach. The iron sliced through the rough with minimal resistance, flew high and landed on the front of the green. Again the ball flew dead straight without my normal cut.
To make a long story short I was astonished at the ease of this game improvement iron. Before my Mizunos and many moons ago I played three years on the golf team in school with an 11 handicap. Naturally I thought I was ready for a better player irons and really have not enjoyed the MP60s (based on my ability). I agree that I should test out irons before making any type of purchase but I am overly eager to replace my irons. Since many companies don't offer their full lines in lefty versions I have been researching the Mizuno JPX825, Nike VRS Convert 2.0, TM Speedblade and Ping G25 & Karsten.
Any feedback on these irons? I must admit after hitting the Taylormade Brand these irons are definitely to be highly considered. Price is really not a factor in these sets since they are all priced under $1K.