Bests & Worsts Reviews from Amazon

On May 21st, my new Sunny bike arrived, after reading the instruction booklet a couple of times and checking to make sure all parts had arrived I put it together in about 1 1/2 hours. This bicycle is very heavy duty and sturdy - I had to walk the package into the house as it was much to heavy for me to lift. My test ride was 2 miles with using the hand grips and it was great with no knee pain - but definitely butt pain. I had been using a cane off and on for the past 3 years and the last 6 months using it constantly, so my doctor prescribed physical therapy for 2 months (twice a week) to build up my muscles around my knee to prepare for possible knee replacement.. I have not been able to use a bicycle for over 5 years because of knee pain. My first day of therapy I was unable to use a bicycle for warm-up - after 10 sessions I am now able to use a bicycle for 5 minutes warm-up. This gave me the resolve to get my own exercise bicycle to use especially when weather is too windy or hot to walk. After checking many on-line and store exercise bicycles and carefully reading reviews, I decided on this Sunny Health Fitness Foldable Semi-Recumbent Bicycle with arm pulls and a leg pull. I chose this bicycle because it had the something to work my arms; has a good size seat - not the little ones; has a backrest which is an extra safety precaution for me with my balance issues; takes a small footprint and can easily be folded up and moved; has a large display for time, speed, distance, calories and rpm; and the majority of reviews were very good. Next day, I road 5 continuous miles in 30 minutes, working my arms for about 10 minutes, and afterwards my leg raises. Of course, right now I am at the lowest level of tension both for riding and my arms but I am so happy - I felt it was a good workout - and best of all - NO KNEE PAIN!! Updated 5/25/18: My only con is that after riding about 15 minutes my butt starts hurting. After not being able to find a reasonably priced seat cover to fit this 13" wide 10" long 2 1/2" depth seat and no answer to my question, I finally found an acceptable solution! Walmart Mainstay brand Barstool Cushion at 13" round, it's cushioned and has elastic all around. Our local store had them in red and they are located by other chair cushions. It fits great with no adjustments needed. Okay it's not perfect I do slide a little but just reposition myself a few times - and best part I was able to ride for 45 minutes today and no butt pain! Updated 6/4/18: Well, I found a gel seat cover that fits it's by Derriair (link below). I don't slide, it was easy to put on, there is a bit of extra gel cover in the front but it just hangs down, very comfortable and well made, only con it is $60 including postage. Since I ride daily I decided it would be worth it. I contacted Derriair before buying and they said it would it and it does; I also contacted Sunny Health and they referred me to a seat which I believe is the same. So if you want a gel seat cover - https://smile.amazon.com/gp/product/B000MW2B08/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1 Update 6/11/18: A clicking noise has started.