Last year I bought a CBR 843, 7' Medium, great great rod. However, I found wanting a little when using larger deeper running cranks with a lot of resistance. I throw a lot of these cranks and wanted to match the big cranks with the right rod. I would consider a Rapala DT16 as a larger crank. Casts a mile.

The CBR 845 is also 7' but a med/heavy.

The CBR 903 is 7.5' a medium.

The CBR 906 is 7.5' a med/heavy.

I'm thinking the 845 7' Med/Heavy is a sure solution, but if I can gain a few yards by stepping up to a 7.5', why not? If so, which one? Is the 903 going to be just a little longer version of my 843 or will it have a little more backbone to handle larger cranks, or should I just get the 906 7.5' Med/Heavy and be done with it? Great rods. Really pleased with the 843. So, any one using any of the above?

For any crankbait that dives deeper than 12 feet (or maybe even 10 feet), I feel you only have two good choices when it comes to G Loomis Crankbaits rods.  Those two choices are the CBR847 or the CBR896DF.  I have the CBR855 (very similar to the CBR845) and anything diving deeper than 10 feet is pushing it, in my opinion.  I had the CBR906 and though it might be able to handle deeper diving crankbaits, the rear handle is just too short.  I just purchased the CBR896DF and the rear handle is at a good length and it feels it will have the power to fish deeper diving crankbaits.  Therefore, to help save you the expense and any aggravation, if you are looking for a G Loomis crankbait rod for deep diving crankbaits, I would stick to one of the two I mentioned. 

my advice for buying g.loomis rods is to read the descriptions and then buy one power UP from what you think you need. if you think the 845 sounds just right for your needs, then buy the 847. i have an 845 and it fishes more like what i would expect the 843 to fish like based on the description.

as for the 7.5' rods, been there and done that. with people to going to 8-footers, i thought 7.5' would be worth a try so i bought 3 7.5' crankin' rods and i just don't like them...difficult to get in and out of my rod locker and i found i could cast just as far with my 7-footers. but, that's just me...obviously, others LOVE the longer rods.

Just the kind of info I was lookin for. Thanks guys.

I have the 845 and have to agree that it's not a true DD rod. I love mine for mid-range cranks, but I don't believe it has enough power for the real DD. I do however believe it is the best all around crankbait rod available. If you want the extra length, I would say go with the 906.

The 843 is no match for a true deep diving crankbait. Killer rod for mid-range cranks though. If I was in your situation, I'd opt for a longer rod in MH and like LCman said, get the longer handle.

The 903 feels more like a noodle than the 843 for sure.  It would make a great rod for trolling bandit crankbaits or something like that, but it has very little backbone.  The only downfall of the 906 is the shorter handle length - but the blank is very good for a DT-16 and handles a DD22 pretty well also.  The 906 makes an amazing lipless crank rod as well!