New to pool ownership and am looking to buy first robot. Think I'm leaning toward a dolphin. Looked through the threads here and the m400 looks like a good choice. I can get for 1125 with the rebate. Dolphin has a number of others in the sub-1000 range--triton, nautilus, etc. which also get good recommendations. I am overwhelmed with the info out there and am looking for some expert opinion as to whether the extra money is worth it. I have a 20x40 concrete pool with some steps and quarter moon bump outs at either end. Would appreciate any thoughts and suggestions.