To celebrate the 35th anniversary of GunPla a new subseries within the HG line is being released that updates models from yesteryear with modern proportion and new engineering. The first of these releases is the Guncannon, which started the HGUC line in 1999.
I love this current release of the model! It's intended to be easier to assemble, doesn't require glue or paint and is quite articulated when completed. Plus this mecha is part of the trio of mechas from the very first Gundam series. This is the supporting mecha to the Gundam RX-78 along with the Gundam guntank.