eastern performance cycles has the 11" chrome lowering air shocks at 199.00 everyday. ive had them on my electra glide classic for 4 years now.
i wouldnt risk my life on the lowering blocks to save 100 bucks..

 

I have the 1 1/2 lowering blocks, I weigh 220 and wife weighs 140 with bags loaded to the max and 25 lbs in factory rear shocks have NEVER bottomed out either. Running an Elite-3 MU90B16 Rear tire.

 

I second the TJ Products 1" lowering blocks. They are an easy install and fit nice on my 09 RKC. You won't have to shim the leather bags on a 09-10. They are great quality and most important do not change the angle of the shocks. The ride is the same because you use your stock 13" shocks. The 12" shock will give you a harsher ride. I'v put 1000 miles on them and haven't bottomed out once. The bike is now much easier for me when riding 2 up. They are kind of pricey ($150) but well worth it.
Best mod I have done yet.