I still like the basic Morningstars.
Temp. compensated, true PWM, easy, reliable, cheap, and etc. The De-Sulfator concept is based on these patents. An expensive knock-off of the cheap original. Some wholesale companies quit suppling them for a while because of the B.S. Check Sandia labs. True PWM puts more power into a battery at the end of the average day. Less gassing and water use too. Why spend $150 for a doo-hicky copy if the original does more for less money?
Battery temp is important. Thats why you get a temp chart with the floating ball turkey baster battey testers. Check with the battery manufacturers. Try to get a Trace temp. probe for the cost of a complete Morningstar for a small system. A SG-4 can be had for $30, if you pick it up I'll give it to you for $25, temp comp. and all (how much is a Trace temp probe again?)
Pro's and con's? Check the Sandia labs papers. May have to dig deep. True PWM is much better. It's in there.
Trackers offer 'up to 30% more', by following the sun. The gain would be offset by that same money in more panels in most places, in most systems. Simple enough with a calculator. BTW, some major companies no longer handle tracker BS because they just don't work like claimed.
Max Power Point has some good points. Mostly with water pumps, given what it does and what it costs. It can put a few extra amps into a 12v battery when the supply is at 9v. For solar, this only happens a few minutes per average day (without constant drain, like a stalled, shorted pump motor).
Rated watts divided by 17v should give about peak amps for a factory PV module.
Get your PV panels to about 20-22v open circuit (for a 12v system). Get a controller rated for at least that much (Isc and Voc). Make sure it is for that much continuous (fine print BS). Check the warrenty. Check the failure rate. Call tech support to see if they can speak anything close to English, and if they are even still in bussiness.
Make the panels first. I'd go with 38 cells if possible(there is a reason they are surplus).
Big job. Look for at charge control systems when they are done.