Let's Compare - Bosconian

[TrekMD]

Bosconian is a free-roaming multi-directional scrolling shooter arcade game which was developed and released by Namco in Japan in 1981. In North America, it was manufactured and distributed by Midway Games. In contrast to the more linear shooter games from its time period, Bosconian allows the player's ship to freely roam across open space which scrolls in all directions. The game also featured a radar, which tracks the position of the player's ship, the formation attacks, and the space stations. It uses Namco Galaga hardware, but with a video system like that used in Rally-X. Bosconian went on to win the 1982 Arcade Award for Best Science Fiction/Fantasy Coin-Op Game in January 1983, beating both Atari Games's Gravitar and Sega's popular Zaxxon for the award.

Source:  Wikipedia

https://www.youtube.com/watch?v=IUgRNaA_uLA

[Shadowrunner]

Great game! I don't think I ever tried it in the arcade but I played a lot of this on the Namco collection on the PS1. All of the ports look pretty good.

[TrekMD]

The 2600 clone is really great.  It's not finished but it plays really good.