Which ignition box are you running and did you have to splice the wires into your stock ignition, buy an adapter plug or did it hook right up?
I had an MSD 6AL on my last car and it was nice but I was told I need one of the newer digital ignitions on my Formula.
Could you tell any difference after installing it?

 

With only mild mods you won't see much, if any, benefit of an aftermaket ign system.

If you must get one, I'd recommend the MSD Digital6+ with the optional harness that makes it a plug-n-play install.

 

I,ve been running an Accel 300+ for about 5 years now with no problems, plug and play install as well.

 

Running the 6AL, had to buy adapter (25 bucks) or had option of splicing. Had trouble revving smoothly after cam swap, this fixed it.

 

I've had the 6AL before and I couldn't tell one bit of a difference. No difference in gas mileage and no noticeable difference of any kind. (including HP)

They're also known to ruin optis due to the higher voltage output. I'd spend the money elsewhere.

My 2 copper.

 

Both of my cars have an ignition, one an Accel 300+ and the other a MSD Digital 6+. Both are nice pieces of work, both work great. Since both cars are head/cammed, I can tell a difference in the idle/rev quality with the stock vs. box setup.

 

I ran around with a 6A for a while, took it off, noticed no difference. I'm with Madwolf - spend your money on something with a little better return for the investment. Unless you're running some naaawws, I'd skip it and just concentrate on keeping the plugs, wires, coil, etc fresh.