L28 shares its design with the L25
...which I owned (1981). They were designed to be maxi-trailerables with a broad keel that is formed into the hull. On the inside of the boat there is a depression to provide head room. You are actually walking in the keel. There still isn't a lot of room inside.
The wide shallow keel is a negative from a performance perspective compared to other boats of the same length, especially upwind. The hull to deck joint is screwed and glued rather than through-bolted (at least it was on my 25) which most would view as a negative. The interior was pretty well made, although I hated the vinyl head liner as it blocked access to anything mounted to the deck and makes leaks hard to trace.
On the plus side, it is trailerable and L28's tend to be inexpensive. However you need to recognize that you are getting less boat that a boat of similar size without the design issues, in my opinion. My L25 was less than a stellar performer, especially to windward. Moving from it to my 9.2A was like trading in a pinto for a camaro.
Focus on what you will use it for 80% of the time. My L25 was inexpensive and had a large enough cockpit to take out guests on day sails. She was $1000 without a trailer. She got me out on the water and allowed me to prove to myself that it was worth moving up. She was lousy in light air and lousy in any type of sea (> 1-2 ft) but I had some good times on her.