So I purchased the top box kit when it first came out. I installed it myself being I had it shipped from a dealer in another state. Installation wasn't bad. Though it did not come with instructions I think it is pretty easy to figure out if you are handy. It was a little complicated by some bolts not lining up as they should and required me drilling some new holes. I wasn't crazy about having to leave off the nice silver side panels when you attach the rack. It looks like the design of the SRS has fixed this issue. All in all I like the rack. It is a nice size without being too big. Great to just take off my helmet and gloves and lock them up quickly. Even fully loaded with a case of beer and groceries, I found it did not adversely affect handling. I added the optional backrest and brake light (both ordered on Amazon at discounted price). The brake light added a little time to the install but I like it. It is pretty easy to tap the brake wire under the pinon seat. The case is pretty well made but very plain. I like how easily it comes off the rack if I wanted to leave it off. The attached photo is not great but only one I have with the case on.
As for other accessories, they have been slow in coming out. I am calling my dealer every week to pester him to get me pricing and availability on the peg lowering kit, centerstand and power tank. It seems that Zero is not really up to speed with accessories for the SRF. You can just look for their missing accessory page on their website to tell. Other than that I added the following third party accessories: Deflector Windsheild, Cortech tank bag, Rox handlebar risers, mirror extenders, screen protector for the dashboard, Ram mount phone and dashcam holders. And I am still on the fence about ordering the corbin seat. It may end up being a choice between powertank or seat. So as always, the original price of the bike was only the beginning of my money pit. Hope this helps you.