I really recommend the Comet SBB5.  This is a 2 meter and 440 antenna.  It does not require a ground plane.  It is almost double the length of the SBB2 which is an awful antenna.   My SWR analyzer showed a near perfect SWR for 2 meters using the SBB5.  Typically this antenna is attached to a vehicle.  I volunteered to provide communications for a walk and run event at a local university.  From past experience working this event, I found that the tall cement and steel buildings that stand like mountains between me and the event control operator posed attenuated signal strength.   Using an improved antenna is one solution to ensure clear communications.  You can not walk around using the antenna.  Typically each operator is assigned a fix position along the walk run walk routes.   The event starts at 7am and finishes at 11am.  I am not going to stand for 4 hours.  I decided to bring a beach chair.  I also took the ProLine MS220CR microphone stand and attached a TRAM Model 3270 to the end of the mic stand so I could screw in my antenna.  I also had a ABR Industries 6 foot RG316/U with SMA Male connector to allow me to use my HT radio with this antenna.  I can thus sit in my chair and transmit using a superior antenna at a raised elevation.

Antenna is Recommended.