A buddy of mine has a 6.0 and is wanting some gauges. He is wanting the Insight CTS, but another friend of ours has a Banks IQ w/ Six gun for an LMM. He will sell the banks IQ for 200 bucks or 300 for everything, he was wanting to get just the monitor for 200. Will it work without the six gun? Is the CTS worth the extra $200? Thanks alot