BCS vs GTS: Which is the Better Game System?

About Last Blitzkrieg: Wacht am Rhein, The Battle of the Bulge, from BoardGameGeek:

Last Blitzkrieg is the first entry in the new Series: Battalion Combat Series (MMP), which simulates combat in World War II (and beyond) at the battalion scale. Its subject is the German Ardennes offensive Wacht Am Rhein (the Battle of the Bulge) on four detailed maps (at 1km per hex) and with 1,680 counters. Last Blitzkrieg covers the battle in a level of detail rarely seen before and does so in a very playable manner. The BCS itself was designed to show that battalion level combat is its own subject, being neither "small divisions" nor "large platoons". The results may surprise some players, but will hopefully pique the interest of all and allow them to see many things they thought they already knew in a fresh light. Key Battalion Combat Series concepts include: Objectives Recon Units Concentrated Armor and Support Prepared Defense MSRs and Combat Trains Set Piece Combats vs. Shock Attacks vs. Engagements Artillery Barrages Artillery Asset Points Attack by Fire SNAFU Activation by Formation Traffic and Coordination Fatigue Memory Markers Last Blitzkrieg also adds: Bridge Blowing Greif Teams Weather Tiger Maintenance Woes Voraus Units Game play commences on 16 December 44 and ends on 31 December 44 (with each turn being one day) allowing the first phase of the Allied counterattack to proceed. The winner is determined by comparing the German high water mark in Victory Point hexes against the situation at the very end of the game. In addition to the full campaign, which uses a 4-map "box" layout, there are 9 additional scenarios for a total of 10 scenarios of various sizes: Two 4-map scenarios: Last Blitzkrieg Campaign: 16 turns Final Blitzkrieg: 10 turns Two 2-map scenarios: Breakthrough Campaign: 6 turns using Maps C and D Advance & Destroy: 10 turns using Map D and a portion of Map B Six 1-map scenarios (including two scenarios on portions of a single map) Northern Campaign: 6 turns using Map C Southern Campaign: 6 turns using Map D Kampfgruppe Peiper: 5 turns using portion of Map C The Goose Egg: 5 turns using portion of Map C Bastogne: Screaming Eagles Under Siege: 8 turns using portions of Maps B and D (total playing area is less than one map) Tip of the Spear: 4 turns using Map A Last Blitzkrieg was designed to bring all of this-and much more-to your table in a most historically accurate game that is jam-packed with information. The BCS was designed with twin goals: to provide the most insight possible into a battle and to provide games that have maximum playability. Last Blitzkrieg contents: Four 22" x 34" maps Six countersheets One Battalion Combat Series rules booklet One Last Blitzkrieg specific rulebook One Battalion Combat Series Crib Notes booklet Two Battalion Combat Series Charts and Tables booklets Two Last Blitzkrieg Charts and Tables booklets One box and lid Two 6-sided dice (description from MMP website and user)