The DC performance of AlGaN/GaN high electron mobility transistors grown by plasma-assisted molecular beam epitaxy was investigated for gate lengths in the range 0.1-1.2 mum. On 0.25 mum gate length devices we obtained 40 V-DS operation with > 50 mA peak I-D. The peak drain current density was 0.44 A/mm for 100 mum gate width devices with 1.2 mum gate lengths. The extrinsic transconductance (g(m)) decreased with both gate length and gate width and was greater than or equal to 75 mS/mm for all gate widths for 0.25 pin devices. E-beam written gates typically produced a slightly lower Schottky barrier height than optically patterned gates.